Packer actuated vent assembly

ABSTRACT

A packer actuated vent assembly comprising a packer device sattable by reciprocal movement of a mandrel. The vent assembly comprises a barrel attached to the packer body and a mandrel extension having a valve means thereon. The valve means engages a stop member on the barrel and is moved to the venting position when the mandrel of the packer is properly manipulated to seat the packer.

United States Patent [1 1 Vann et al.

1 1 Mar. 18, 1975 1 1 PACKER ACTUATED VENT ASSEMBLY [73] Assignee: VannTool Company, Inc., Artesia,

N. Mex.

122] Filed: July 26. 1973 1211 Appl. Nu: 382,958

I52] US. Cl. 166/128, 166/133 1 Int. Cl E21b 33/12 [58] Field of Search166/126, 128, 133, 142, 166/145, 152

[56] References Cited 1 UNITED STATES PATENTS 3,098,526 7/1963 Heron166/133 X 3,211,228 10/1965 Bramlett t 166/128 3,211,229 10/1965Bramlett 166/128 3,211,231 10/1965 Bramlett 166/128 X 3,433,301 3/1969MCEver 166/128 3,457,994 7/1969 Stachowiuk t t 166/128 X 3,482,62812/1969 Griffin 166/152 Primary E.ramt'nerDavid H. Brown Attorney,Agent, or FirmMarcus L. Bates [57] ABSTRACT A packer actuated ventassembly comprising a packer device settable by reciprocal movement ofamandrel. The vent assembly comprises a barrel attached to the packerbody and a mandrel extension having a valve means thereon. The valvemeans engages a stop mem her on the barrel and is moved to the ventingposition when the mandrel of the packer is properly manipulated to seatthe packer.

11 Claims, 12 Drawing Figures PATENTEU 7 8W5 71.87 1.448 sum 1 or 4 FIGIPATENTEDHAR 1 19m a? 1 448 snmso g FIG. 5

PATENTEU 1 81975 sum u if A FIGII 1 PACKER ACTUATED VENT ASSEMBLYBACKGROUND OF THE INVENTION In completing a hydrocarbon producingformation in a deep well. various completion techniques require that atubing string be attached to a retrievable packer and that a perforatinggun be suspended from a vent string with the vent string being supportedfrom the retrievable packer. Upon perforating the hydrocarbon producingformation, it has heretofore been necessary to utilize a wireline inorder to open the perforated nipple of the vent string so that flow fromthe completed formation can flow up the tubing annulus into theperforated nipple, and up the production string to the surface of theearth.

In addition to the trip made into the hole with the wireline to operatethe vent string, it is often necessary to additionally employ a blankingplug in order to enable various other manipulative operations to becarried out on the borehole prior to the act of completion. Installationand retrieval of the blanking plug calls for a round trip with awireline operated fishing tool.

Making a trip into a borehole with a wireline is costly as well asdangerous because anything put into the hole is a calculated riskinasmuch as there is always a danger of losing the apparatus in thehole, and hence a costly fishing job.

Where a conventional wireline operated perforated nipple is employed,there is sometimes more than [2.000 psi pressure differential across thesliding sleeve and for this reason difficulty is often experienced inforcing the sliding sleeve to move to the open position by a wirelineoperated fishing tool. Moreover, in some well completion techniques, itis often desirable to perforate simultaneously with the opening of theperforated nipple. This expedient is not possible where a wireline isused to effect communication because a considerable time delay isexperienced while the wireline is being removed from the borehole andbefore the perforating gun can be fired.

For these and many other reasons peculiar to well completion and wellwork-over operations, it is desirable to be able to run a packerdownhole with a vent assembly being disposed in underlying relationshipto the packer, and with the vent assembly supporting various downholeequipment. such as a jet perforating gun. It is desirable that such avent assembly be actuated by the tubing string in a manner whereby thefinal act of setting the packer actuates the vent assembly to the openedposition thereby enabling a flow path to be immediately establishedbetween a production zone and a surface flow line upon peforation of theformation.

SUMMARY OF THE INVENTION This invention relates to downhole tools andspecifi' cally to a packer actuated vent string comprised of a packerassembly anchored downhole in a borehole which has a mandrel axiallymovable relative to the packer body for setting the packer elementsagainst the borehole wall by manipulation of the tubing string connectedto the mandrel of the packer. The packer body and the packer mandreleach have an extension connected thereto and downwardly dependingtherefrom. A valve means is connected to provide flow into the mandrelextension. Means are connected to the packer body extension formanipulating the valve means when 2 the packer mandrel is moved relativeto the packer body.

In the preferred embodiment of the present invention, a sliding valveassembly is sealingly received about a marginal length of the mandrelextension. while a stop means inwardly projects from the packer bodyextension, so that when the tubing string is set down, the mandreltelescopes in a downward direction thereby enabling the stop means toengage the valve means and move the valve to the flow permittingconfiguration.

In another form of the invention. means are provided for closing thevalve means whenever the tubing string is picked up a sufficient amount.

A primary object of the present invention is the pro vision of a packeractuated vent assembly which can be moved to the flow conductingconfiguration by manip ulation of apparatus associated with the packer.

Another object of the invention is to provide a packer actuated ventassembly comprised of a retrievable packer having the vent assemblydisposed thereunder so that manipulation of the tubing string to whichthe packer is connected causes the vent assembly to be moved to the openposition.

A further object of this invention is to disclose and provide a means bywhich a permanent completion well bore apparatus can be run downholeinto the borehole while the tubing string ofthe apparatus is utilized toset a packer apparatus and at the same time to open a vent stringunderlying the packer means.

A still further object of this invention is to provide a new combinationof elements comprised of a well borc packer and a tubing-vent stringconnected together in a manner whereby manipulation of the tubing stringin setting the packer also causes the vent string to be moved to theflow conducting configuration.

Another and still further object of this invention is to provide amethod for completing a hydrocarbon hear ing formation wherein theformation can be perforated immediately following setting of the packerand the acl of setting the packer is utilized for opening the ventstring.

An additional object of the present invention is to provide a method ofopening a vent string located downhole in a borehole by utilizing themovement ol the tubing string required in setting the packer.

These and various other objects and advantages of the present inventionwill become readily apparent to those skilled in the art upon readingthe following de tailed description and claims and by referring to theac companying drawings.

The above objects are attained in accordance with the present inventionby the provision of a method of actuating a vent apparatus with a packerapparatus wherein the apparatus is fabricated in a manner sub stantiallyas described in the above abstract and summary.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 2 is an enlarged. sideelevational view of part of the apparatus of FIG. 1 which discloses oneembodi ment of the present invention;

FIG. 3 is an enlarged, broken. part cross-sectional side view of part ofthe apparatus disclosed in FIG. 2;

FIG. 4 is a broken, part cross-sectional representa tion of theapparatus disclosed in FIG. 3;

FIG. 5 shows the apparatus of FIG. 4 in a different operativeconfiguration;

FIG. 6 is a cross-sectional view taken along line 66 of FIG. 3;

FIG. 7 is a cross-sectional view taken along line 77 of FIG. 3;

FIG. 8 is a broken, part cross-sectional, side elevational view of partof the apparatus disclosed in the foregoing figures;

FIG. 9 is a top plan view of the apparatus of FIG. 8 taken along thelines indicated by the numerals 9-9;

FIG. I0 is a broken, side elevational view ofa modification of part ofthe apparatus disclosed in FIGS. 3-5;

FIG. I] is a fragmentary, part cross-sectional representation of stillanother embodiment of the present in vention; and.

FIG. 12 is a cross-sectional view taken along line I2-l2 of FIG. ll.

DETAILED DESCRIPTION OF THE INVENTION In FIG. I there is disclosed thesurface of the ground 6 having a well head 8 connected to theillustrated borehole. Within the borehole there is disclosed a packer 12connected to a packer actuated vent assembly 14 made in accordance withthe present invention.

The packer 12 can take on any number of different forms so long as it isprovided with a hollow mandrel for flow conducting fluid axiallytherethrough. and so long as the mandrel is reciprocated relative to thepacker body while the packer is being set. As for example. a BakerLok-Set retrievable casing packer. product No. 642-l2 page 498, BakerOil Tool [970-7] catalog, Baker Oil Tools, Los Angeles, Calif. Otherpacker apparatus which can be used with the present invention areexemplified by the patent to Brown. US. Pat. No. 1893.492, or Keithahn.No. 3.! l2,795.

As illustrated in FIG. I. in conjunction with some of the remainingfigures of the drawings. interface I6 delines a shoulder of a threadedconnection effected by the lower threaded marginal terminal end of thepacker body and the upper threaded marginal terminal end of the ventassembly. Sub 17 is attached to coupling member I8 of the mandrel of thepacker so that the packer can be series connected and supported by theillustrated tubing string. The lower edge portion 19 of the mandrelcoupling is movable towards the upper body portion 20 of the packeruntil the lower edge portion 19 abuts upper edge portion 21, therebycausing the packer rubbers 22 to be set within the casing. Radiallydisposed slips 24 and 26 are forced in an outward direction by movementof the mandrel so as to anchor the packer device to the interior surfaceofthe casing wall. Drag blocks 28 discourage movement of the packer bodyrelative to the casing while the mandrel is being manipulated.

The vent assembly ofthe present invention comprises a cylindrical barrel30 having spaced radial slots 32 formed intermediate the downwardlyopening peripheral edge portion 34 and the interface 16. The lowermarginal end of the mandrel extension 36 threadedly engages a sub orcoupling 38 for connection of the vent assembly into a pipe string 40 sothat a jet gun 42 or the like can be run downhole into the borehole andpositioned adjacent to a hydrocarbon containing formation when it isdesired to complete the well.

Looking now to the details of FIGS. 3 to 9, in conjunction with variousones of some of the remaining figures, the mandrel extension is seen tobe provided with spaced parallel circumferentially extending grooves 44and 46 formed in a marginal exterior wall surface thereof. A pluralityof radially spaced apart apertures 48 are formed through the wall of themandrel in indexed relationship with one another and with the spacedgrooves.

A valve means in the form of a cylindrical sleeve which forms a slidingvalve element 50 is provided with a close tolerance inside peripheralsurface 51 which sealingly and slidably engages a marginal length of themandrel in proximity to the apertures 48. Where desired, spaced sealmeans may be interposed adjacent to the apertures between the insideperipheral wall sur face SI and the outer peripheral wall surface of themandrel, rather than relying upon a close tolerance sliding seal. Suchan expedient is illustrated in FIG. II.

The outer peripheral wall surface 52 of the sliding valve element isspaced inwardly from the interior surface of the barrel a sufficientamount to avoid undue pressure drop offluids flowing through the beforemen tioned slots. Radially spaced apart in-turned latch means 60 definethe terminal end of a plurality of fin gers, each formed by the spacedcutouts 6] which 21ft milled into the upper marginal end of the sleeve.

A plurality of ports 62 are radially spaced from one another and formedthrough the wall of the sleeve in indexed relationship with one another,and with the ap ertures 48 of the mandrel, and with the grooves 44 and46. Lower shoulder 63 ofthe sleeve is spaced from the grooves and thethreaded plug or stop means 64 a criti' cal amount as will be betterappreciated later on in this disclosure. Passageway 65 is formed throughthe plug and loosely receives the lower mandrel extension 36 in atelescoping manner tlierethrough.

Apertures 66 extend through the wall of the barrel so that a fastenermeans 68 in the form of a screw can be placed therethrough and intothreaded engagement with the adjustable stop means. Upper face 70provides an annular area, a portion of which is brought into en gagementwith sleeve shoulder 63 when the mandrel 36 or 18 is moved in a downwarddirection a sufficient amount to cause the former to abuttingly engagethe latter.

In the embodiment of FIG. I0, which sets forth a modification of themandrel disclosed in the foregoing embodiments, the uppercircumferentially extending groove has been elongated in a longitudinaldirection to reduce the critically of the relative motion or travel ofthe packer mandrel in relationship to movement of the sleeve member.

Looking now to the details of the embodiment disclosed in FIGS. 11 and12, wherein whenever it is possible or logical to do so. like or similarnumerals refer to like or similar numerals or elements corresponding tothe foregoing figures of the drawings. The vent assembly II4 has anupper end portion which threadedly engages the diagrammaticallyillustrated packer ll2. Packer mandrel I8 is threadedly engaged by themandrel extension 136 of the present invention, as in the beforedescribed embodiment. Ports I32 provide a flow path through the barrel130. Coupling member 38 can be related to the coupling member of FIG. 2.The

mandrel 136 slidably and sealingly engages the slidable sleeve 150within the limits provided by the circumferentially extendingenlargement 160 and its co-acting spaced stop means. Ports 162 areradially spaced about a marginal length of the mandrel. Lower terminalend 163 of the sleeve abuttingly engages circumferentially disposedenlargement 175 of the mandrel when the sleeve is positioned to closethe ports in the illustrated manner of FIG. 11.

A plurality of inwardly turned spaced latch means 164 depend from andform the lower marginal end portion of the barrel and are madecomplementary respective of the lower concave face of the enlargement160 so that the latch 164 is received within the co-actingcircumferentially disposed concavity formed within the enlargement 160.Shear pin 177 precludes inadvertent relative motion between the sleeveand the mandrel extension.

Seal means are provided which prevent fluid flow into the mandrelextension and are comprised of spaced seals 178, 179 which sealinglyengage a marginal length of the inside peripheral wall surface of thesleeve and the outer peripheral wall surface of the mandrel. Abutment176 is affixed to the interior wall surface ofthe barrel and can bebrought into abutting engagement with the upper face of the enlargement160 when the mandrel extension is moved in an upward direction relativeto the barrel.

In operation of the embodiment seen in FIGS. 3-9, a retrievable packer,such as a Baker Lok-Set Packer, is attached to the vent assembly of thepresent invention by threadedly engaging the barrel of the vent assemblywith a lower threaded marginal portion of the packer body, andthreadedly engaging the mandrel extension with the packer mandrel sothat the barrel and packer extension are fitted to the retrievablepacker to provide a new combination of co-acting elements. The mandrelextension is series connected in a tubing string with a perforating gununderlying the vent assembly in a manner to enable the gun to bepositioned adjacent to one or more hydrocarbon producing formations. Thepacker actuated vent assembly is run into the hole to the proper depthwhereupon the upper tubing string is turned a specified number ofrevolutions so as to set the slips olthe packer against the casing wall.After the packer device has been firmly anchored within the borehole.the tubing string can be set down with any force desired. Generally,setting down 6,000 pounds of tubing weight sets the upper slips andbegins compression of the packing elements. Six to ten thousand poundsof downward thrust effected by the tubing string on the packer ratchetsthe mandrel through a lock ring to complete and lock the expanded packerrubbers. Should it be desired to release the packer, 3,000 to 6,000pounds up-strain and rotation to the right will release the tool so thatit can be retrieved or moved to another location in the borehole.

As the packer mandrel moves in a downward direction, lower edge 19abuttingly engages upper edge portion 21 of the packer body while at thesame time shoulder 63 of the sleeve engages face 70 of the stop means,and is moved to the open position. Accordingly, the distance between thespaced grooves and the distance between the shoulder and the face of thestop means, when added together, should be an amount exactly equal tothe relative movement measured between edge portion 19 and 21 of thepacker assembly.

As the mandrel moves relative to the barrel, shoulder 63 abuttinglyengages stop means 64 thereby causing the in-turned latch means to bedisengaged from the lower groove and relocated in the upper groove 44.Movement of the sliding sleeve in an upward direction brings the ports62 and apertures 48 into indexed relationship with one another whereuponflow now proceeds through slots 32, ports 62, apertures 48, and into theinterior of the hollow mandrel where the flow continues through thepacker mandrel, into the tubing string, and to the surface of the earth.

Upon retrieval of the apparatus from the borehole. the configuration ofthe valve means will be in the form of FIG. 5. Therefore, the in-turnedlatches may be repositioned within the lower groove 46 as illustrated inFIG. 4, and the packer actuated vent assembly can then be used inanother borehole.

[n the operation of the embodiment disclosed in FIGS. 11 and 12,relative movement between the mandrel and the barrel causes the latchmeans 164 to engage the underside of enlargement 160 thereby movinglower edge portion 163 in an upward direction relative to the mandrelextension until the lower edge portion clears ports 162, therebyenabling production flow to occur from the lower borehole annulus,through the ports 162, into the interior of the mandrel extension.through the packer mandrel, and up through the tubing string to thesurface of the earth. Should the packer be retrieved from the borehole,movement of the packer mandrel in an upward direction relative to thepacker body brings the upper face of enlargement 160 into abuttingengagement with upper stop means 176, thereby moving the sliding sleevein a downward direction relative to the mandrel extension, until thelower terminal end 163 abuttingly engages the circumferentiallyextending shoulder 175, thereby closing ports 162.

Those skilled in the art, having digested the foregoing disclosure, willappreciate that the longitudinal travel from 19 to 21 of the packer bodyand mandrel must be equal to the distance as measured from the latchmeans 164 to the enlargement together with the distance between edgeportion 163 and the uppermost of ports 162 in order for manipulativeaction of the tubing string to properly actuate the valve means of thevent assembly.

The packer assembly 12 used in combination with the present invention isadapted to be anchored down hole in a borehole and has a mandrel l8axially movable respective to a packer body 20. The tubing string 40' isconnected to the packer mandrel for conducting fluid flow from theborehole located below the packer to the surface of the ground. Thepacker actuated vent assembly 14 of the present invention has a hollowmandrel extension 36, a valve means 50, a barrel 30 con centricallyarranged relative to one another with the valve means being in the formof a sliding sleeve which slidably engages the mandrel extension insealed relationship therewith, and with the barrel being radially spacedfrom the sliding valve means and from the mandrel.

The upper marginal end of the barrel and the man drel are threadedlyengaged with co-acting threaded surfaces of the packer body and mandrelto provide means by which the upper end of the mandrel exten sion andbarrel can be attached to the lower end of the packer mandrel and packerbody. The stop means 64 on the barrel engages and moves the slidingvalve as sembly so that when the sleeve is moved from the lower groove,or flow preventing position, into the upper groove. or flow permittingposition, the mandrel extension is moved relative to the barrel. Thisexpedient enables the packer to be set by moving the packer mandrelrelative to the packer body, and at the same time the mandrel extensionis moved relative to the barrel of the vent assembly. thereby causingmeans on the barrel to move the sliding valve means to the flowpermitting position.

In permanently completing a hydrocarbon containing formation byutilization of the present invention, those skilled in the art, havingread the foregoing disclosure. will appreciate that the packer can beset with the minimum weight required, the perforating gun fired bydropping a go-devil down the tubing string, and the packer actuated ventassembly can be opened instantaneously or simultaneously at the jetcharges are fired, thereby enabling produced fluid from the newformation to freely flow to the surface of the earth at the instant theperforations are formed in the formation.

The present invention eliminates at least one wireline trip into thewell, and provides a tremendous available force by which the valve meansof the vent assembly can be actuated to the flow permittingconfiguration.

We claim:

1. In a packer assembly adapted to be anchored downhole in a borehole,and having a mandrel axially movable respective to a packer body forsetting a packer element against the borehole wall, with a tubing stringconnected to the mandrel for conducting fluid flow from the boreholelocated below the packer to the surface of the ground, in combination;

a packer actuated vent assembly, said vent assembly having a hollowmandrel extension, a sliding valve means. and a barrel;

said mandrel extension. sliding valve means, and barrel beingconcentrically arranged relative to one another with said sliding valvemeans slidably engaging a marginal length of said mandrel extension insealed relationship therewith, and with said barrel being radiallyspaced from said sliding valve means and from said mandrel; aperturemeans in said marginal length of said mandrel extension so that a flowpath is formed from the interior to the exterior thereof;

means by which the upper end of said mandrel exten sion and barrel,respectively. can be attached to the lower end of the packer mandrel andpacker body. respectively;

means on said barrel for engaging and moving said sliding valve meansfrom a flow preventing to a flow permitting position when said mandrelextension is moved relative to said barrel;

so that when the packer is set by moving the mandrel ofthe packerrelative to the packer body. said mandrel extension is moved relative tosaid barrel, causing said means on said barrel to move said slidingvalve means to the flow permitting position.

2. The packer actuated vent assembly of claim 1 wherein said slidingvalve means is a cylindrical sleeve slidably received in sealedrelationship about 21 marginal length of said mandrel extension, portsformed in said sleeve. said aperture means being aligned with said portswhen said sleeve is moved into the flow permitting position, saidaperture means being misaligned with said ports when said sleeve is inthe flow preventing position;

said mandrel extension is provided with longitudinally spaced detents;said sleeve having latch means formed thereon for releasably engagingsaid spaced detents;

the relative position of said spaced detents, said latch means, saidports, and said aperture means being arranged whereby when said latchmeans is in one of said spaced detents. said valve means is in the flowpreventing position, and when said latch means is in the remaining ofsaid detents, said valve means is in the flow permitting position;

said means on said barrel for engaging and moving said valve meansincludes a stop means, said stop means and said sleeve being positionedrelative to one another so that the movement of the packer mandrel insetting the packer imparts movement into the mandrel extension formoving the sleeve into the flow permitting position.

3. The packet actuated vent assembly of claim 1 wherein said slidingvalve means is a cylindrical sleeve slidably received in sealedrelationship about said marginal length of said mandrel extension, portsformed in said sleeve, said aperture means being aligned with said portswhen said sleeve is moved into the flow permitting position, saidaperture means being misaligned with said ports when said sleeve is inthe flow preventing position.

4. The packer actuated vent assembly of claim 3 wherein said means onsaid barrel for engaging and moving said valve means is a stop means.said stop means and said sleeve being positioned relative to one anotherso that the movement of the packer mandrel in setting the packer impartsmovement into the mandrel extension for moving the sleeve into the flowpermitting position.

5. The packer actuated vent assembly of claim 3 wherein said mandrelextension is provided with longitudinally spaced detents; said sleevehaving latch means formed thereon for releasably engaging said spaceddetents;

the relative position of said spaced detents, said latch means, saidports, and said aperture means being arranged whereby when said latchmeans is in one of said spaced detents. said valve means is in the flowpreventing position, and when said latch means is in the remaining ofsaid detents, said valve means is in the flow permitting position.

6. A packer actuated vent assembly comprising a packer device having abody, a packer element, a hollow mandrel, and means by which the packerdevice can be anchored downhole in a well bore. said mandrel beingmovable relative to the packer body for setting the packer element whichprecludes fluid flow across the packer device;

a barrel attached to and extending from the body, a mandrel extensionattached to and extending from said hollow mandrel in series flowrelationship therewith, aperture means in said mandrel exten sionforming a flow path from the interior to the exterior thereof; a valvemeans connected to said mandrel extension for causing a fluid flow pathto be formed from without to within said mandrel extension when saidvalve means is moved from a flow preventing to a flow permittingposition;

and means responsive to relative movement between said barrel and saidmandrel extension for moving said valve means from said flow preventingto said flow permitting position.

7. The packer actuated vent assembly of claim 6 wherein said valve meansis a cylindrical sleeve slidably received in sealed relationship about amarginal exterior length of said mandrel extension, said aperture meansforming at least one aperture in said mandrel extension, a port formedin said cylindrical sleeve, said aperture being aligned with said portwhen said sleeve is moved into the flow permitting position, saidaperture being misaligned with said port when said cylindrical sleeve isin the flow preventing position;

said mandrel is provided with spaced detents; said cylindrical sleevehaving latch means formed thereon for releasably engaging said spaceddetents;

the relative position of said spaced detents, said latch means, saidport, and said aperture being arranged whereby when said latch means isin one of said spaced tletents, said valve means is in the flowpreventing position, and when said latch means is in the remaining ofsaid detents, said valve means is in the flow permitting position;

said means responsive to relative movement between said barrel and saidmandrel extension is a stop means located on said barrel, means on saidcylindrical sleeve for engaging said stop means, said stop means andsaid means on said sleeve being positioned relative to one another sothat movement of the hollow mandrel while setting the packer deviceimparts movement into the mandrel extension for moving the cylindricalsleeve into the flow permitting position.

8. The packer actuated vent assembly of claim 6 wherein said valve meansis a cylindrical sleeve slidably received in sealed relationship about amarginal exterior length of said mandrel extension, said aperture meanscomprising apertures formed in said marginal length of said mandrelextension, ports formed in said cylindrical sleeve, said apertures beingaligned with said ports when said cylindrical sleeve is moved into theflow permitting position, said apertures being misaligned with saidports when said cylindrical sleeve is in the flow preventing position.

9. The packer actuated vent assembly of claim 8 wherein said meansresponsive to relative movement between said barrel and said mandrelextension is a stop means located on said barrel, means on saidcylindrical sleeve for engaging said stop means, said stop means andsaid means on said cylindrical sleeve being positioned relative to oneanother so that movement of the hollow mandrel while setting the packerdevice imports movement into the mandrel extension for moving thecylindrical sleeve into the flow permitting position.

10. The packer actuated vent assembly of claim 8 wherein said mandrelextension is provided with spaced detents; said cylindrical sleevehaving latch means formed thereon for releasably engaging said spaceddetents;

the relative position of said spaced detents, said latch means, saidports and said apertures being arranged whereby when said latch means isin one of said spaced detents, said valve means is in the flowpreventing position, and when said latch means is in the remaining oneof said detents, said valve means is in the flow permitting position.

11. A packer assembly for being anchored downhole in a borehole, andhaving a hollow mandrel axially movable respective to a packer body forsetting a packer element against the borehole wall, with a tubing stringbeing connected to the mandrel for conducting fluid flow from the lowerborehole to the surface of the ground, in combination:

a packer actuated vent assembly, said vent assembly having a hollowmandrel extension, a sliding valve element, a barrel, and an actuatorfor said sliding valve element;

said mandrel extension, sliding valve element, and

barrel being concentrically arranged with said sliding valve elementslidably engaging a marginal longitudinally extending length of saidmandrel extension is sealed relationship therewith, apertures formed insaid mandrel extension, said barrel being radially spaced from saidsliding valve means and from said mandrel; an annular area formed between said barrel and said mandrel extension;

means by which said mandrel extension and barrel, respectively, can beattached to the packer man drel and packer body, respectively;

said actuator being an inwardly directed abutment formed on said barrelfor engaging and moving said sliding valve element from a flowpreventing to a flow permitting position when said mandrel extension ismoved relative to said barrel;

so that when the packer is set by moving the mandrel of the packerrelative to the packer body, said mandrel extension is moved relative tosaid barrel, causing said abutment on said barrel to move said slidingvalve element to the flow permitting position; whereupon fluid flow canoccur from the interior of the mandrel extension, through saidapertures, and into said annular area.

1. In a packer assembly adapted to be anchored downhole in a borehole,and having a mandrel axially movable respective to a packer body forsetting a packer element against the borehole wall, with a tubing stringconnected to the mandrel for conducting fluid flow from the boreholelocated below the packer to the surface of the ground, in combination; apacker actuated vent assembly, said vent assembly having a hollowmandrel extension, a sliding valve means, and a barrel; said mandrelextension, sliding valve means, and barrel being concentrically arrangedrelative to one another with said sliding valve means slidably engaginga marginal length of said mandrel extension in sealed relationshiptherewith, and with said barrel being radially spaced from said slidingvalve means and from said mandrel; aperture means in said marginallength of said mandrel extension so that a flow path is formed from theinterior to the exterior thereof; means by which the upper end of saidmandrel extension and barrel, respectively, can be attached to the lowerend of the packer mandrel and packer body, respectively; means on saidbarrel for engaging and moving said sliding valve means from a flowpreventing to a flow permitting position when said mandrel extension ismoved relative to said barrel; so that when the packer is set by movingthe mandrel of the packer relative to the packer body, said mandrelextension is moved relative to said barrel, causing said means on saidbarrel to move said sliding valve means to the flow permitting position.2. The packer actuated vent assembly of claim 1 wherein said slidingvalve means is a cylindrical sleeve slidably received in sealedrelationship about a marginal length of said mandrel extension, portsformed in said sleeve, said aperture means being aligned with said portswhen said sleeve is moved into the flow permitting position, saidaperture means being misaligned with said ports when said sleeve is inthe flow preventing position; said mandrel extension is provided withlongitudinally spaced detents; said sleeve having latch means formedthereon for releasably engaging said spaced detents; the relativeposition of said spaced detents, said latch means, said ports, and saidaperture means being arranged whereby when said latch means is in one ofsaid spaced detents, said valve means is in the flow preventingposition, and when said latch means is in the remaining of said detents,said valve means is in the flow permitting position; said means on saidbarrel for engaging and moving said valve means includes a stop means,said stop means and said sleeve being positioned relative to one anotherso that the movement of the packer mandrel in setting the packer impartsmovement into the mandrel extension for moving the sleeve into the flowpermitting position.
 3. The packer actuated vent assembly of claim 1wherein said sliding valve means is a cylindrical sleeve slidablyreceived in sealed relationship about said marginal length of saidmandrel extension, ports formed in said sleeve, said aperture meansbeing aligned with said ports when said sleeve is moved into the flowpermitting position, said aperture means being misaligned with saidports when said sleeve is in the flow preventing position.
 4. The packeractuated vent assembly of claim 3 wherein said means on said barrel forengaging and moving said valve means is a stop means, said stop meansand said sleeve being positioned relative to one another so that themovement of the packer mandrel in setting the packer imparts movementinto the mandrel extension for moving the sleeve into the flowpermitting position.
 5. The packer actuated vent assembly of claim 3wherein said mandrel extension is provided with longitudinally spaceddetents; said sleeve having latch means formed thereon for releasablyengaging said spaced detents; the relative position of said spaceddetents, said latch means, said ports, and said aperture means beingarranged whereby when said latch means is in one of said spaced detents,said valve means is in the flow preventing position, and when said latchmeans is in the remaining of said detents, said valve means is in theflow permitting position.
 6. A packer actuated vent assembly comprisinga packer device having a body, a packer element, a hollow mandrel, andmeans by which the packer device can be anchored downhole in a wellbore, said mandrel being movable relative to the packer body for settingthe packer element which precludes fluid flow across the packer device;a barrel attached to and extending from the body, a mandrel extensionattached to and extending from said hollow mandrel in series flowrelationship therewith, aperture means in said mandrel extension forminga flow path from the interior to the exterior thereof; a valve meansconnected to said mandrel extension for causing a fluid flow path to beformed from without to within said mandrel extension when said valvemeans is moved from a flow preventing to a flow permitting position; andmeans responsive to relative movement between said barrel and saidmandrel extension for moving said valve means from said flow preventingto said flow permitting position.
 7. The packer actuated vent assemblyof claim 6 wherein said valve means is a cylindrical sleeve slidablyreceived in sealed relationship about a marginal exterior length of saidmandrel extension, said aperture means formiNg at least one aperture insaid mandrel extension, a port formed in said cylindrical sleeve, saidaperture being aligned with said port when said sleeve is moved into theflow permitting position, said aperture being misaligned with said portwhen said cylindrical sleeve is in the flow preventing position; saidmandrel is provided with spaced detents; said cylindrical sleeve havinglatch means formed thereon for releasably engaging said spaced detents;the relative position of said spaced detents, said latch means, saidport, and said aperture being arranged whereby when said latch means isin one of said spaced detents, said valve means is in the flowpreventing position, and when said latch means is in the remaining ofsaid detents, said valve means is in the flow permitting position; saidmeans responsive to relative movement between said barrel and saidmandrel extension is a stop means located on said barrel, means on saidcylindrical sleeve for engaging said stop means, said stop means andsaid means on said sleeve being positioned relative to one another sothat movement of the hollow mandrel while setting the packer deviceimparts movement into the mandrel extension for moving the cylindricalsleeve into the flow permitting position.
 8. The packer actuated ventassembly of claim 6 wherein said valve means is a cylindrical sleeveslidably received in sealed relationship about a marginal exteriorlength of said mandrel extension, said aperture means comprisingapertures formed in said marginal length of said mandrel extension,ports formed in said cylindrical sleeve, said apertures being alignedwith said ports when said cylindrical sleeve is moved into the flowpermitting position, said apertures being misaligned with said portswhen said cylindrical sleeve is in the flow preventing position.
 9. Thepacker actuated vent assembly of claim 8 wherein said means responsiveto relative movement between said barrel and said mandrel extension is astop means located on said barrel, means on said cylindrical sleeve forengaging said stop means, said stop means and said means on saidcylindrical sleeve being positioned relative to one another so thatmovement of the hollow mandrel while setting the packer device importsmovement into the mandrel extension for moving the cylindrical sleeveinto the flow permitting position.
 10. The packer actuated vent assemblyof claim 8 wherein said mandrel extension is provided with spaceddetents; said cylindrical sleeve having latch means formed thereon forreleasably engaging said spaced detents; the relative position of saidspaced detents, said latch means, said ports and said apertures beingarranged whereby when said latch means is in one of said spaced detents,said valve means is in the flow preventing position, and when said latchmeans is in the remaining one of said detents, said valve means is inthe flow permitting position.
 11. A packer assembly for being anchoreddownhole in a borehole, and having a hollow mandrel axially movablerespective to a packer body for setting a packer element against theborehole wall, with a tubing string being connected to the mandrel forconducting fluid flow from the lower borehole to the surface of theground, in combination: a packer actuated vent assembly, said ventassembly having a hollow mandrel extension, a sliding valve element, abarrel, and an actuator for said sliding valve element; said mandrelextension, sliding valve element, and barrel being concentricallyarranged with said sliding valve element slidably engaging a marginallongitudinally extending length of said mandrel extension is sealedrelationship therewith, apertures formed in said mandrel extension, saidbarrel being radially spaced from said sliding valve means and from saidmandrel; an annular area formed between said barrel and said mandrelextension; means by which said mandrel extension and barrel,respectively, can be attached to the packer mandrel and paCker body,respectively; said actuator being an inwardly directed abutment formedon said barrel for engaging and moving said sliding valve element from aflow preventing to a flow permitting position when said mandrelextension is moved relative to said barrel; so that when the packer isset by moving the mandrel of the packer relative to the packer body,said mandrel extension is moved relative to said barrel, causing saidabutment on said barrel to move said sliding valve element to the flowpermitting position; whereupon fluid flow can occur from the interior ofthe mandrel extension, through said apertures, and into said annulararea.